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What does |= (single pipe equal) and &=(single ampersand equal) mean
...gnment operators, translating (very loosely)
x |= y;
into
x = x | y;
and the same for &. There's a bit more detail in a few cases regarding an implicit cast, and the target variable is only evaluated once, but that's basically the gist of it.
In terms of the non-compound operators, & ...
Why would one omit the close tag?
...of the file. The header problem seems irrelevant in the following context (and this is the only good argument so far):
14 ...
What is difference between Collection.stream().forEach() and Collection.forEach()?
I understand that with .stream() , I can use chain operations like .filter() or use parallel stream. But what is difference between them if I need to execute small operations (for example, printing the elements of the list)?
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adb command not found
I need to run an adb forward command before I could use the ezkeyboard application which allows user to type on the phone using browser.
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Git's famous “ERROR: Permission to .git denied to user”
I have tried googling and read through https://help.github.com/en/articles/connecting-to-github-with-ssh and various, various guides. I am unable to git push -u origin master or git push origin master ( the same command ).
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find: missing argument to -exec
I was helped out today with a command, but it doesn't seem to be working. This is the command:
10 Answers
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How do I test if a variable is a number in Bash?
... the regex appropriately; for instance:
^[0-9]+([.][0-9]+)?$
...or, to handle numbers with a sign:
^[+-]?[0-9]+([.][0-9]+)?$
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Java to Clojure rewrite
...argish (50,000 single lines of code) Java application (a web app using JSP and servlets) in Clojure. Has anyone else got tips as to what I should watch out for?
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what exactly is device pixel ratio?
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Short answer
The device pixel ratio is the ratio between physical pixels and logical pixels. For instance, the iPhone 4 and iPhone 4S report a device pixel ratio of 2, because the physical linear resolution is double the logical linear resolution.
Physical resolution: 960 x 640
Logical resolutio...
Convert column classes in data.table
... dt[, Quarter:=as.character(Quarter)]
str(dtnew)
Classes ‘data.table’ and 'data.frame': 10 obs. of 3 variables:
$ ID : Factor w/ 2 levels "A","B": 1 1 1 1 1 2 2 2 2 2
$ Quarter: chr "1" "2" "3" "4" ...
$ value : num -0.838 0.146 -1.059 -1.197 0.282 ...
Using lapply and as.charac...